The present invention relates to a drum for storing and dispensing a coiled material wound on the drum in a clipping machine, in particular a sausage clipping machine.
In particular, the invention relates to a drum for storing and dispensing a coiled material wound on the drum, in particular a line of clips, the drum comprising a drum body having a hub and side walls respectively disposed at the axial end faces of the hub, the side walls extending beyond the outer circumferential surface of the hub in the radial direction. The storage space defined by the inner facing surfaces of the side walls and the hub and that extends circumferentially around the hub is used to accommodate the coiled material.
It is known, in practice, that when producing sausage products the sausage meat is fed by a filling machine to a clipping machine via a filling tube. In the clipping machine, the filling material is filled into a tubular casing material that is closed at one end by a first clip, and the tubular casing material is closed by placing a second clip. Each pair of closing tools comprises an upper die and a lower die, between which the clip is shaped during closure until the minimum distance between the closing tools is reached. After clipping, the closing tools are returned to their initial or open position. The casing material of the resultant sausage product is then separated from the remaining supply of casing material, and the finished sausage product is carried out of the clipping machine.
Such a closure must meet high quality standards. On the one hand, it must not be so firm that the casing is damaged during closure. On the other hand, however, the closure must be sufficiently secure and tight so that the clip does not slip off the casing material and/or that sausage meat does not escape from the casing material when the sealed sausage is subjected to further subsequent processing such as cooking, smoking, etc.
When the clipping machine is to be used for many different sausage products using a number of different casing materials, different clips are applied that differ in respect of both their material and their dimensions (leg length and thickness of material). For this reason, closing tools are used that match the particular clip type being applied, in order to achieve a precisely defined deformation of the clip during closure.
To ensure that the production process can be carried out at high cycle rates without interruption, a large number of clips must be provided at the clipping machine. In practice, this is done by providing clips in the form of an metal strand pressed into a corrugated shape and wound on a drum, the clips being joined at the ends of their side legs to form a single strand. The clip required in each case is separated from the coil of clips and closed by means of the closing tools.
Since the closing tools and the clips match each other in size, it is also necessary to replace the closing tools whenever the clip size is changed, for example to make sausage products having a different calibre. To simply this matching and to exclude operating errors, the closing tools and the drum storing the coiled line of clips are provided with labels containing information about the tool and the clip, respectively.
Such a system is described in DE 10 2005 033 437 (U.S. Pat. No. 7,325,380). The drum on which a respective line of clips is coiled is fitted with an RFID tag. Clip information, such as clip size, clip material, etc., is stored on said tag. The information can be retrieved by a reading device provided on the clipping machine, and forwarded to the control system for the clipping machine. RFID tags are likewise applied to the closing tools belonging to the clipping machine, these tags containing information about the closing tool, in particular about the clip that can be processed by the tool. This information can likewise be retrieved by a reading device provided on the clipping machine, and forwarded to the control system for the clipping machine. The controller, or more precisely a comparison circuit in the controller, compares the retrieved information about the closing tools and about the clip supply and supplies a compatibility signal to the controller of the clipping machine. When the compatibility of the clip and the tool has been established, a start signal is outputted and the production process can begin.
However, these known drums have disadvantages. For example, an RFID tag applied to the drum body can be very easily removed or be damaged by moved machine parts, thus hindering or preventing the information from being retrieved. Furthermore, if the RFID has detefective shielding, retrieving the information is more difficult, or the information gets corrupted.